U.S. patent application number 09/992768 was filed with the patent office on 2002-06-20 for preparation of vinyl-containing macromers.
Invention is credited to Markel, Eric J..
Application Number | 20020077434 09/992768 |
Document ID | / |
Family ID | 21893724 |
Filed Date | 2002-06-20 |
United States Patent
Application |
20020077434 |
Kind Code |
A1 |
Markel, Eric J. |
June 20, 2002 |
Preparation of vinyl-containing macromers
Abstract
Polymeric compositions of matter are described comprising olefin
polymer chains having M.sub.n of about 400 to 75,000, a ratio of
vinyl groups to total olefin groups according to the formula 1
vinyl groups olefin groups [ comonomer mole percentage + 0.1 ] a
.times. 10 a .times. b ( 1 ) where, a=-0.24 and b=0.8, and where
the total number of vinyl groups per 1000 carbon atoms is greater
than or equal to 8000.div.M.sub.n. The invention includes a method
for preparing these polymeric products comprising contacting one or
more olefin comonomers with a catalyst system containing a
transition metal catalyst compound and an alumoxane wherein the
aluminum to transition metal ratio is from 10:1 to less than or
equal to 220:1 (AL:Me). The process conditions of the invention
permit predictable macromer characteristics of both molecular
weight and vinyl unsaturation.
Inventors: |
Markel, Eric J.; (Kingwood,
TX) |
Correspondence
Address: |
ExxonMobil Chemical Company
P.O. Box 2149
Baytown
TX
77522
US
|
Family ID: |
21893724 |
Appl. No.: |
09/992768 |
Filed: |
November 6, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09992768 |
Nov 6, 2001 |
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09521043 |
Mar 8, 2000 |
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09521043 |
Mar 8, 2000 |
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09020138 |
Feb 6, 1998 |
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60037323 |
Feb 7, 1997 |
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Current U.S.
Class: |
526/160 ;
526/282; 526/348.7; 526/943 |
Current CPC
Class: |
C08L 23/0815 20130101;
C08L 51/06 20130101; C08L 2314/06 20130101; C08F 2/08 20130101;
C08L 23/02 20130101; C08L 23/08 20130101; C08L 55/005 20130101;
Y10S 526/942 20130101; C08F 210/18 20130101; C08L 23/08 20130101;
C08F 290/00 20130101; C08L 2205/02 20130101; C08L 55/00 20130101;
C08F 257/02 20130101; C08F 255/02 20130101; C08L 55/005 20130101;
C08L 23/0815 20130101; C08F 210/18 20130101; C08F 297/08 20130101;
C08F 290/042 20130101; C08F 297/083 20130101; C08L 23/02 20130101;
C08F 110/02 20130101; C08L 2666/04 20130101; C08F 2500/12 20130101;
C08F 2500/03 20130101; C08L 2666/24 20130101; C08F 2500/12
20130101; C08L 2666/04 20130101; C08F 2500/09 20130101; C08F 210/08
20130101; C08L 2666/02 20130101; C08F 2500/09 20130101; C08F 110/02
20130101; C08F 255/00 20130101; C08F 290/044 20130101; C08F 290/04
20130101 |
Class at
Publication: |
526/160 ;
526/282; 526/348.7; 526/943 |
International
Class: |
C08F 004/44 |
Claims
I claim:
1. A composition of matter comprising olefin polymer chains having
M.sub.n of about 1500 to 75,000, a ratio of vinyl groups to total
olefin groups according to the formula 4 vinyl groups olefin groups
[ comonomer mole percentage + 0.1 ] a .times. 10 a .times. b ( 1 )
where, a=-0.24 and b=0.8, and where the total number of vinyl
groups per 1000 carbon atoms is greater than or equal to
8000.div.Mn.
2. The composition of claim 1 wherein a=-0.20.
3. The composition of claim 1 wherein a=-0.18 and b=0.83.
4. The composition of claim 1 wherein a=-0.15 and b=0.83.
5. The composition of claim 1 wherein said olefin polymer comprises
one or more of the group consisting of ethylene, C.sub.3C.sub.12
.alpha.-olefins, isobutylene and norbornene.
6. A method for preparing polymers having high levels of vinyl
unsaturation comprising contacting one or more olefin monomers with
a catalyst solution composition containing a transition metal
catalyst compound and an alumoxane wherein the aluminum to
transition metal ratio is from 10:1 to 220:1.
7. The method of claim 6 wherein the aluminum to transition metal
ratio is from 20:1 to 140:1.
8. The method of claim 6 wherein the aluminum to transition metal
ratio is from 20:1 to 100:1.
9. The method of claim 6 wherein the transition metal catalyst
compound is one of a Group 4, 5, 6, 7, 8, 9, 10 metal that is
capable of activation with alumoxane for olefin polymerization.
10. The method of claim 9 wherein the transition metal catalyst
compound is a biscyclopentadienyl Group 4 metal compound.
11. The method of claim 9 wherein the transition metal catalyst
compound is a monocyclopentadienyl Group 4 metal compound.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a method for the
preparation of vinyl-containing macromers from olefins utilizing
transition metal catalyst compounds with alumoxane co-catalyst
activators.
BACKGROUND OF THE INVENTION
[0002] Vinyl-terminated polymers, including for the purposes of
this application oligomers, homopolymers and copolymers synthesized
from two or more monomers, are known to be useful for
post-polymerization (or post-oligomerization) reactions due to the
available ethylenic unsaturation at one polymer one chain end or
both. Such reactions include addition reactions, such as those used
in grafting other ethylenically unsaturated moieties, and further
insertion polymerization where the vinyl-terminated polymers are
copolymerized with other monomers such as .alpha.-olefins and/or
other insertion polymerizable monomers. In this latter instance the
vinyl-terminated polymers are often called macromonomers, or
macromers.
[0003] Early work with metallocene transition metal catalyst
compounds activated with alkylalumoxanes such as methylalumoxane
led to observations that their use in olefin polymerization gave
rise to unsaturated end-groups in a greater percentage of polymer
produced than had typically been true of insertion polymerization
using traditional, pre-metallocene Ziegler-Natta catalysts. See
EP-A-0 129 638 and its U.S. patent equivalent U.S. Pat. No.
5.324.800. Later work by Resconi, et al, reported in Olefin
Polymerization at Bis(pentamethylcyclopentadienyl)zirc- onium and
-hafnium centers. Chain-Transfer Mechanisms, J Am. Chem. Soc.,
1992, 114, 1025-1032, yielded the observations that the use of
bis(pentamethylcyclopentadienyl) zirconcene or hafnocene in
propylene oligomerization favors .beta.-methyl elimination over the
more commonly expected .beta.-hydride elimination as the means for
chain transfer, or polymer chain termination. This was based on
observations that the ratio of vinyl-end groups to vinylidene-end
groups was in the range of 92 to 8 for the zirconocene and 98 to 2
for the hafnocene.
[0004] In addition to these observations, WO 94/07930 addresses
advantages of including long chain branches in polyethylene from
incorporating vinyl-terminated macromers into polyethylene chains
where the macromers have critical molecular weights greater than
3,800, or, in other words contain 250 or more carbon atoms.
Conditions said to favor the formation of vinyl terminated polymers
are high temperatures, no comonomer, no transfer agents, and a
non-solution process or a dispersion using an alkane diluent.
Increase of temperature during polymerization is also said to yield
.beta.-hydride eliminated product, for example while adding
ethylene so as to form an ethylene "end cap". This document goes on
to describe a large class of both mono-cyclopentadienyl and
bis-cyclopentadienyl metallocenes as suitable in accordance with
the invention when activated by either alumoxanes or ionizing
compounds providing stabilizing, noncoordinating anions. The
examples all illustrate the use of the Lewis acid activator
tris(perfluorophenyl) boron with bis(cyclopentadienyl) zirconium
dimethyl at a polymerization temperature of 90.degree. C.
Copolymerization was conducted with ethylene and the two macromers,
respectively, using the same catalyst systems as used to form the
macromers.
[0005] Branched ethylene macromers are described in WO 95/11931.
According to this disclosure vinyl groups are to be greater than 75
mol. % more preferably greater than 80 mol. %, of the total
unsaturated groups, and the weight average molecular weight is said
to be in the range of 100 to 20,000. The method of manufacture of
the described macromers is said to be with a transition metal
compound containing metals of groups 3 through 10, cyclopentadienyl
derivatives of group 4, 5, and 6 are said to be of satisfactory
utility in this regard. These transition metal compounds are also
said to capable of forming ionic complexes suitable for
polymerization by reacting with ionic compounds, alumoxane or Lewis
acids. The ratio of the transition metal component to the alumoxane
component is said to be desirable when at 1/10 to 1/10,000, or most
preferably 1/30 to 1/2000. Examples 1 and 7 illustrate ethylene
macromer preparation with ratios of alumoxane compound to
transition metal compound of 240 and 2000, respectively.
[0006] Various patents address the use of metallocene catalysts
with varying levels of activating alumoxane cocatalysts. One such
is U.S. Pat. No. 4,752,597 where relatively hydrocarbon-insoluble
solid reaction products of metallocenes and alumoxane are prepared
by reacting the two in a suitable solvent where aluminum metal to
transition metal molar ratios are between 12:1 to 100:1. The solid
reaction product is then removed. This solid reaction product is
said to be useful for gas phase, slurry and solution
polymerization.
[0007] Additional art addresses the preparation of chain-end
unsaturated polymers with various metallocenes under various
conditions, each of vinyl-, vinylidene-, vinylene- and
trisubstituted-unsaturation resulting from the reported processes.
The difficulty in determining by standard characterization methods
(.sup.1H-NMR or .sup.13C-NMR) the total of saturated chain ends has
resulted in acceptance in the art of characterizing unsaturated
end-group by the fraction of the total of each type of unsaturation
to the total unsaturated ends. However, industrially efficient
methods of production would greatly benefit from high unsaturated
end group concentrations to the total end group population. that is
including the saturated ends. Thus, the reported variations in
molecular weight distributions and the inability to accurately
determine or predict the resulting type of chain ends, or the less
favored production of unsaturated chain-ends other than those of
vinyl, limits the utility of the prior art. Vinyl-chain ends are
generally accepted to be more reactive to chain-end
functionalization and insertion in subsequent polymerization
reactions than are the other types and are more highly preferred.
Accordingly additional work was undertaken to improve the
vinyl-chain terminated polymer preparation process, its
predictability and its utility for use in the preparation of
branched polymers.
SUMMARY OF THE INVENTION
[0008] The invention comprises an olefin polymerization reaction
product having olefin unsaturation that is predominantly vinyl. In
these reaction product compositions the molar concentration of
vinyl groups is greater than or equal to 50% of the total polymer
chain molar concentration. More specifically, as calculated from
gel permeation chromatography (GPC) and differential refractive
index (DRI) measurements, the invention is a polymeric reaction
product composition of matter comprising olefin polymer chains
having number-average molecular weights ("M.sub.n") from about 400
to about 75,000, a ratio of vinyl groups to total olefin groups
satisfying the formula 2 vinyl groups olefin groups [ comonomer
mole percentage + 0.1 ] a .times. 10 a .times. b ( 1 )
[0009] where, a=0.24, and b=0.8
[0010] and, where the total number of vinyl groups per 1000 carbon
atoms is greater than or equal to 8000.div.M.sub.n. It also
includes a surprisingly, highly efficient method for preparing
polymers having high levels of vinyl unsaturation comprising
contacting one or more olefin monomers with a catalyst solution
composition containing a transition metal catalyst compound and an
alumoxane wherein the aluminum to transition metal ratio is from
10:1 to 220:1. Vinyl-containing chain yields at levels of greater
than 70% of the total unsaturated chains can be achieved while
simultaneously achieving high yields of unsaturated chains in the
total polymer chains as calculated from GPC and NMR. Thus, use of
the process conditions of the invention permits predictable
macromer characteristics of both molecular weight and the vinyl
unsaturation which further enable the preparation of branched
polymers having tailored characteristics suitable for improved
processing applications, for example where melt processing is
either required or industrially preferred, and in polymer blends
where the choice of macromer monomer or comonomer constituents can
lead to improved compatibilities or other characteristics of the
polymer blend.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 illustrates the examples 1-24 of the application in
showing the vinyl yields as a percentage of total olefinic groups
in the polymer products and their relationship in a accordance with
formula (1), below. The vinyl groups were characterized in
accordance with .sup.1H(NMR) methods as described in the
application.
DETAILED DESCRIPTION OF THE INVENTION
[0012] The polymeric macromer compositions of matter according to
the invention are the polymeric chain reaction products of
insertion or coordination polymerization of olefinic monomers.
Means of achieving high proportions of vinyl containing chains
relative to the total number of unsaturated chains in the
polymerization reaction products were effectively achieved, levels
reached greater than 80% vinyl containing chains, and even greater
than 90%. The highest levels, above 90% or even 95%, were achieved
with ethylene homopolymers. For copolymers the vinyl chain levels
were dependent upon the ratio of ethylene to comonomer as defined
in equation (1). The polymeric compositions or reaction products
contain chains with narrow polydispersities, from 1.5 to about 6,
typically 2 to 4, or even 2 to 3.5.
[0013] The number-average molecular weight (M.sub.n) of the
invention polymeric macromers typically range from greater than or
equal to 400 Daltons to less than 80,000 Daltons, more preferably
less than 60,000 Daltons, most preferably less than or equal to
50,000 Daltons.
[0014] In the formula (1) above the values of a and b are within
the preferred ranges expressed in Table A.
1 TABLE A a b -0.20 0.8 -0.18 0.83 -0.15 0.83 -0.10 0.85
[0015] The total number of vinyl groups per 1000 carbon atoms of
the polymeric reaction product is typically greater than 0.13 and
less than 9.85.
[0016] The polymeric compositions of matter thus described exhibit
higher numbers of vinyl containing chains for the total polymeric
reaction product, including both polymer chains having saturated
groups and those with unsaturated groups. Accordingly, these
polymer products can be effectively used for subsequent reactions
where reactive vinyl groups are needed. A measure of this
effectiveness of the invention polymeric products is illustrated by
the observed reaction efficiencies, that is yield of sought
reaction products of functionalized reactions or macromer
copolymerization reactions. The greater the overall vinyl group
content, the greater is the yield of functionalized polymer or the
yield of macromer-branch containing copolymers.
[0017] A broad range of the invention polymeric reaction products
containing vinyl macromers, including homopolymers, copolymers and
polymers containing three or more monomer types, can be synthesized
using the catalyst compositions of the present invention. Thus, the
monomers polymerized using these catalysts include, but are not
limited to: ethylene, C.sub.3-C.sub.18 .alpha.-olefins,
isobutylene; cyclic olefins, e.g., norbornene, methyl-norbornene,
cyclopentene; styrene, non-conjugated dienes and cyclic dienes. As
suggested by this list, any comonomer copolymerizable with ethylene
by coordination or insertion polymerization will be suitable in
accordance with the invention. Such further include: internal
olefins, such as 1-butene; substituted olefins, such as
3-methyl-1-pentene; multiply substituted olefins, such as
3,3-dimethyl-1-hexene and aromatic olefins. The assembly of
monomers in the polymeric reaction products is not limited only to
random copolymers or mixtures of random copolymers. It is known in
the art that the sequence of monomer and comonomers in the chains
can be controlled to impart useful properties by use of various
means, for example, fluxional catalysts or sequential
polymerization processes.
[0018] The method for preparing the polymeric vinyl-containing
macromer product of the invention involves contacting one or more
olefin monomers with a catalyst solution composition containing a
transition metal catalyst compound and an alumoxane at preferred
aluminum to transition metal ratios. The catalyst solution
preparation typically comprises contacting the alumoxane activator
with the transition metal compound in a suitable solvent so as to
form a solution of activated catalyst. Toluene is a preferred
solvent for the catalyst solution in view of the high solubility of
alumoxane and many the transition metal compounds that are suitable
as catalysts when activated in it. Other solvents capable of
solvating to a significant extent both of the activator and the
transition metal compound, as can be readily determined
empirically, will also be suitable. Both of aliphatic and aromatic
solvents will be suitable so long as the transition metal compound
and the alumoxane activator are substantially soluble at the mixing
temperatures utilized.
[0019] The method of preparation for the polymeric vinyl-containing
macromer product of the invention depends principally upon the
molar ratio of aluminum in the alkyl alumoxane activator to
transition metal. Preferably that level is .gtoreq.20 and
.ltoreq.175; more preferably .gtoreq.20 and .ltoreq.140; and, most
preferably .gtoreq.20 and .ltoreq.100. The temperature, pressure
and time of reaction depend upon the selected process but are
generally within the normal ranges for the selected process. Thus
temperatures can range from 20.degree. C. to 200.degree. C.,
preferably from 30.degree. C. to 150.degree. C., more preferably
from 50.degree. C. to 140.degree. C., and most preferably between
55.degree. C. and 135.degree. C. The pressures of the reaction
generally can vary from atmospheric to 305.times.10.sup.3 kPa,
preferably to 182.times.10.sup.3 kPa. For typical solution
reactions, temperatures will typically range from ambient to
250.degree. C. with pressures from ambient to 3450 kPa. The
reactions can be run batchwise. Conditions for slurry-type
reactions are similar to solution conditions except reaction
temperatures are limited to the melt temperature of the polymer. In
some reaction configurations, a supercritical fluid medium can be
used with temperatures up to 250.degree. C. and pressures up to
345.times.10.sup.3 kPa. Under high temperature reaction conditions,
macromer product of lower molecular weight ranges are typically
produced.
[0020] Batchwise reaction times can vary from 1 minute to 10 hours,
more preferably 5 minutes to 6 hours, and most typically from 45
minutes to 90 minutes. The reactions can also be run continuously.
In continuous processes the average residence times can similarly
vary from 1 minute to 10 hours, more preferably 5 minutes to 6
hours, and most typically from 45 minutes to 90 minutes.
[0021] The transition metal catalysts suitable in the invention
process for preparing the vinyl macromer- containing reaction
products include one or more transition metal catalyst precursor
compound that has both 1) stabilizing ancillary ligands and 2)
additional ligands which react with alumoxane activators such that
an active transition metal catalyst complex is produced. Preferred
compounds include metallocene compounds containing at least one
ancillary substituted or unsubstituted cyclopentadienyl ("Cp") ring
as ligands of the transition metal. Here substituted means that one
or more of the hydrogen atoms bonded to the ring carbon atoms of
one or both Cp rings is replaced with one or more monovalent
radicals capable of sigma bonding with the ring carbon. Examples
include C.sub.1-C.sub.30 hydrocarbyl radicals and their
counterparts where one or more carbon atoms is replaced with
another Group 14 atom, e.g., Si or Ge. The term "substituted"
includes both 1) bridging or linking radicals that are bonded to
two different Cp ligands or to one Cp ligand and another transition
metal ligand such as a Group 15 or 16 heteroatom ligand, and 2)
fused ring configurations wherein two Cp ring atoms are covalently
linked by substituents as in indenyl and fluorenyl ligands, which
may themselves be further substituted and/or bridged. Examples
include those monocyclopentadienyl and biscyclopentadienyl Group
4-6 compounds known to those skilled in the art as being suitable
for olefin polymerization. For biscyclopentadienyl compounds see,
e.g., U.S. Pat. Nos. 5,324,800, 5,324,801, 5,441,920 and 5,502,124.
For exemplary monocyclopentadienyl metallocene compounds see, e.g.,
U.S. Pat. Nos. 5,055,038, 5,264,505, and copending U.S. Ser. Nos.
08/545,973, filed Oct. 20, 1995, and 08/487,255 filed Jun. 7, 1995
and published as WO 96/00244.
[0022] Additionally included in the definition of metallocene for
purposes of this invention are those cyclopentadienyl-analogs
wherein one or more ring carbon atom is replaced with a Group 14 or
15 heteratom, or in fused ring systems, such as indenyl and
flourenyl, where one or more carbon atom in any of the fused rings
is so replaced. Listing of suitable metallocenes include
essentially any of those available in the patent literature, such
as those listed above, and academic literature relating to olefin
polymerization. including specifically those addressing amorphous,
and semi-crystalline and crystalline homopolymers and copolymers of
more than one monomer. In particular, those documents addressing
polyethylene polymers and copolymers and those addressing
stereoregular higher olefins, such as isotactic and syndiotactic
polypropylene polymers and copolymers contain suitable
descriptions.
[0023] Any of the other transition metal olefin polymerization
catalyst precursor compounds particularly those of the Group 4, 5,
6, 7, 8, 9 and 10 metals, known in the art to be capable of
activation with alumoxane are also suitable, see for example WO
96/23010, U.S. Pat. Nos. 5,504,049, 5,318,935, and co-pending U.S.
Ser. Nos. 08/473,693, filed Jun. 7, 1995, and 60/019626, filed Jun.
17, 1996. All of which are referred to and incorporated by
reference for purposes of U.S. patent practice.
[0024] Reactor configurations suitable for the present invention
include continuous, batch and semi-batch reactors. Solution-phase,
slurry-phase, and supercritical-phase conditions are useful for
olefin polymerization using these catalysts. Additionally,
combinations of the above reactor types in multiple, series
reactors and/or multiple reaction conditions and/or multiple
catalyst configurations are explicitly intended.
[0025] Preferred solvents for solution phase reactions are selected
on the basis of polymer solubility, volatility and safety/health
considerations. Non-polar alkanes or aromatics are preferred. For
supercritical fluid reactions. the reaction medium is generally
composed of polymer. monomer and comonomer with, optionally,
suitable supercritical cosolvents. For slurry reactions the diluent
may be an inert liquid or bulk liquid comonomer. Solvents,
cosolvents and comonomers are typically purified by treatment with
absorbent material including aluminas and molecular sieves.
Impurities can also be deactivated by the addition of suitable
scavengers well known in the art, including but not limited to
metal alkyls and alumoxanes.
Industrial Utility
[0026] Branched polymers wherein at least some of the branches are
derived from the vinyl macromer-containing product of the invention
will be particularly useful, for example, for improved processing
ethylene copolymers having macromer derived branches. Vinyl
macromer incorporation for branched polymer preparation can be
accomplished by adding the invention polymer product into an
insertion polymerization environment with a catalyst compound
capable of bulky monomer incorporation. Such includes the bridged
mono- and biscylopentadienyl metallocene catalyst compounds
suitable for insertion polymerization of such bulky comonomers as
1-octadecene, 3-methyl-1-pentene and cyclic olefins, such as
norbornene. See, for example, U.S. Pat. Nos. 5,324,801, 5,444,145,
5,475,075 and 5,635,573 and international application WO 96/000244.
Other suitable catalyst systems include, but are not limited to,
amido and imido derivatives of the Group 4, 5, 6, 7, 8, 9, and 10
metals described in the documents noted above for the vinyl
macromer-containing polymeric products of the invention. Also, WO
94/07930, addressed in the background, describes the advantages of
macromer incorporation and means of doing so. Each of these
documents is also incorporated by reference for purposes of U.S.
patent practice.
[0027] For both vinyl macromer product and branched copolymer
preparation, it is known that many methods and permutations of the
ordering of addition of macromer and monomer species to the reactor
are possible, some more advantageous than others. For example, it
is widely known in the art that preactivation of the metallocene
with alumoxane before addition to a continuous solution-phase
reactor yields higher activities than continuous addition of
metallocene and activator in two separate streams. Furthermore, it
may be advantageous to control precontacting time to maximize
catalyst effectiveness, e.g., avoiding excessive aging of the
activated catalyst composition.
[0028] Preferred branch copolymers of the invention are ethylene
homopolymers and copolymers of ethylene with two or more
comonomers. The most readily available comonomers are the olefins,
especially propylene, 1-butene, isobutylene, 1-hexene, and
1-octene. Other suitable comonomers include but are not be limited
to: internal olefins, cyclic olefins, substituted olefins, multiply
substituted olefins and aromatic olefins, such as those described
above for the vinyl macromer products. Comonomers are selected for
use based on the desired properties of the polymer product and the
metallocene employed will be selected for its ability to
incorporate the desired amount of olefins. See U.S. Pat. No.
5,635,573 describing various metallocenes suitable for
ethylene-norbornene copolymers and co-pending U.S. application Ser.
No. 08/651,030, filed May 21, 1996 describing monocyclopentadienyl
metallocenes suitable for ethylene-isobutylene copolymers. These
documents are incorporated by reference for purposes of U.S. patent
practice.
[0029] For improved polyethylene film tear, a longer olefin
comonomer, such as 1-octene, may be preferred over a shorter olefin
such as butene. For improved polyethylene film elasticity or
barrier properties, a cyclic comonomer such as norbornene may be
preferred over an olefin. The concentrations of comonomer in the
reactor will be selected to give the desired level of comonomer in
the polymer, most preferably from 0 to 50 mole percent.
[0030] Furthermore. it is possible to react two or more polymeric
macromer chains having the same or different comonomers and/or the
same or different molecular weights to derive new polymer
compositions with desirable properties. We have found that
statistical mixtures or formulated mixtures of the branch/block
molecules derived by the. joining of these macromer chains exhibit
commercially useful properties. Optionally, it is possible to use
dienes to control incorporation of unsaturated chains into other
unsaturated chains.
[0031] Functionalization reactions for low molecular weight vinyl
group-containing polymeric products include those based on thermal
or free radical addition. or grafting, of vinyl-group containing
compounds and ethylenically unsaturated compounds. A typical.
industrially useful example is subsequent grafting reactions with
maleic acid, maleic anhydride or vinyl acids or acid esters, e.g.,
acrylic acid, methyl acrylate, etc. The addition of these groups
allows for additional functionalization through amidation,
immidization, esterification and the like. For example, see, U.S.
Pat. No. 5,498,809 and international publications WO 94/19436 and
WO 94/13715. Each addresses ethylene-1-butene polymers having
vinylidene termination and their functionalization into effective
dispersants in lubricating oil compositions. See also EP 0 513 211
B1 where similar copolymers are described in effective wax crystal
modifier compositions for fuel compositions. The invention
polymeric products useful in this manner typically will have
M.sub.n from about 1,500 to 10,000 M.sub.n preferably about 2,000
to 5,000 M.sub.n. Each of these documents are incorporated by
reference for purposes of U.S. patent practice.
[0032] It is preferable to use the high vinyl-unsaturation
polymeric products of the invention such that they are promptly
functionalized or copolymerized after prepared. The highly reactive
vinyl groups appear to be susceptible to by-product reactions with
adventitious impurities and. even, dimerization or addition
reactions with other unsaturated group-containing polymeric chains.
Thus maintaining in a cooled, inert environment in dilute
concentrations after preparation and prompt subsequent use will
optimize the effectiveness of the use of vinyl macromer product of
the invention. A continuous process utilizing series reactors. or
parallel reactors will thus be effective. the vinyl macromer
product being prepared in one and continuously introduced into the
other.
EXAMPLES
[0033] General: All polymerizations were performed in a 1-liter
Zipperclave reactor equipped with a water jacket for temperature
control. Liquids were measured into the reactor using calibrated
sight glasses. High purity (>99.5%) hexane, toluene and butene
feeds were purified by passing first through basic alumina
activated at high temperature in nitrogen, followed by 13.times.
molecular sieve activated at high temperature in nitrogen.
Polymerization grade ethylene was supplied directly in a
nitrogen-jacketed line and used without further purification.
Clear, 10% methylalumoxane (MAO) in toluene was received from
Albemarle Inc. in stainless steel cylinders, divided into 1-liter
glass containers, and stored in a laboratory glove-box at ambient
temperature. Ethylene was added to the reactor as needed to
maintain total system pressure at the reported levels (semi-batch
operation). Ethylene flow rate was monitored using a Matheson mass
flow meter (model number 8272-0424). To ensure the reaction medium
was well-mixed, a flat-paddle stirrer rotating at 750 rpm was
used.
[0034] Reactor preparation: The reactor was first cleaned by
heating to 150.degree. C. in toluene to dissolve any polymer
residues, then cooled and drained. Next, the reactor was heated
using jacket water at 110.degree. C. and the reactor was purged
with flowing nitrogen for a period of .about.30 minutes. Before
reaction, the reactor was further purged using 10 nitrogen
pressurize/vent cycles (to 100 psi) and 2 ethylene pressurize/vent
cycles (to 300 psi). The cycling served three purposes: (1) to
thoroughly penetrate all dead ends such as pressure gauges to purge
fugitive contaminants. (2) to displace nitrogen in the system with
ethylene, and (3) to pressure test the reactor.
[0035] Catalyst preparation: All catalyst preparations were
performed in an inert atmosphere with <1.5 ppm H.sub.2O content.
In order to accurately measure small amounts of catalyst, often
less than a milligram, freshly prepared catalyst stock
solution/dilution methods were used in catalyst preparation. To
maximize solubility of the metallocenes, toluene was used as a
solvent. Stainless steel transfer tubes were washed with MAO to
remove impurities, drained, and activator and catalyst were added
by pipette, MAO first.
[0036] Macromer synthesis: First, the catalyst transfer tube was
attached to a reactor port under a continuous flow of nitrogen to
purge ambient air. Next, the reactor was purged and pressure tested
as outlined above. Then, 600 ml of solvent was charged to the
reactor and heated to the desired temperature. Comonomer (if any)
was then added, temperature was allowed to equilibrate, and the
base system pressure was recorded. The desired partial pressure of
ethylene was added on top of the base system pressure. After
allowing the ethylene to saturate the system (as indicated by zero
ethylene flow), the catalyst was injected in a pulse using high
pressure solvent. Reaction progression was monitored by reading
ethylene uptake from the electronic mass flow meter. When the
desired amount of macromer had accumulated. ethylene flow was
terminated and reaction was terminated by rapid cooling (.about.1
minute) and addition of an excess of methanol to precipitate the
polymer product. The polymer/solvent mixture was dried in flowing,
ambient air.
[0037] Product characterization: The polymer product samples were
analyzed by gel permeation chromatography using a Waters
150.degree. C. high temperature system equipped with a DRI
Detector, Showdex AT-806MS column and operating at a system
temperature of 145.degree. C. The solvent used was 1,2,4
trichlorobenzene, from which polymer sample solutions of 0.1 mg/ml
concentration were prepared for injection. The total solvent flow
rate was 1.0 ml/minute and the injection size was 300 microliters.
GPC columns were calibrated using a series of narrow polystyrenes
(obtained from Tosoh Corporation, Tokyo, 1989). For quality
control, a broad-standard calibration based on the linear PE sample
NBS-1475 was used. The standard was run with each 16-vial carousel.
It was injected twice as the first sample of each batch. After
elution of the polymer samples, the resulting chromatograms were
analyzed using the Waters Expert Fuse program to calculate the
molecular weight distribution and one or more of M.sub.n, M.sub.w
and M.sub.z averages. Quantification of long chain branching was
performed the method of Randall, Rev. Macromo. Chem. Phys., C29,
(2&3), p. 285-297..sup.1H-NMR analyses were performed using a
500 mHz Varian Unity model operating at 125 .degree. C. using
d.sub.2-tetrachloroethane as solvent. .sup.13C-NMR analyses were
performed using at 100 mHz frequency, a Varian Unity Plus model
under the same conditions.
Example 1
[0038] Catalyst Preparation. A stainless steel catalyst addition
tube was prepared as outlined above. An aliquot of 0.25 milliliters
of 10% methylalumoxane (MAO) solution in toluene was added,
followed by 0.5 milliliters of a toluene solution containing 1
milligrams of Cp.sub.2ZrCl.sub.2, biscyclopentadienyl zirconium
dichloride, per milliliter. The sealed tube was removed from the
glovebox and connected to a reactor port under a continuous flow of
nitrogen. A flexible, stainless steel line from the reactor supply
manifold was connected to the other end of the addition tube under
a continuous flow of nitrogen.
[0039] Homopolymerization. The reactor was simultaneously purged of
nitrogen and pressure tested using two ethylene fill/purge cycles
(to 300 psig)(2170 kPa). Then, the reactor pressure was raised to
.about.40 psig (377 kPa) to maintain positive reactor pressure
during setup operations. Jacket water temperature was set to
90.degree. C. and 600 milliliters of toluene were added to the
reactor. The stirrer was set to 750 rpm. Additional ethylene was
added to maintain a positive reactor gauge pressure as gas phase
ethylene was absorbed into solution. The reactor temperature
controller was set to 90.degree. C. and the system was allowed to
reach steady state. The ethylene pressure regulator was next set to
100 psig (791 kPa) and ethylene was added to the system until a
steady state was achieved as measured by zero ethylene uptake. The
reactor was isolated and a pulse of toluene pressurized to 300 psig
(2170 kPa) was used to force the catalyst solution from the
addition tube into the reactor. The 100 psig (791 kPa) ethylene
supply manifold was immediately opened to the reactor in order to
maintain a constant reactor pressure as ethylene was consumed by
reaction. After 30 minutes of reaction, the reaction solution was
quickly cooled and 200 milliliters of methanol were added to
terminate reaction and precipitate polymer. Product was removed to
an open 2 liter tub and dried in ambient air, yielding 38 grams of
homopolyethylene. A summary of Example 1 reaction conditions is
provided in Table 1.
Examples 2-7.
[0040] Catalyst Preparation. The MAO-activated Cp.sub.2ZrCl.sub.2
catalysts of Examples 2-7 were identical to that of Example 1
except the amounts of catalyst solution (containing 1 milligram
Cp.sub.2ZrCl.sub.2 per milliliter of toluene) and the amounts of
10% MAO in toluene solution used were different. These catalyst
formulations are summarized in Table 1.
[0041] Homopolymerization. Reaction conditions used in Examples 2-7
involved only minor modifications of the conditions used in Example
1. These variations are summarized in Table 1.
Example 8
[0042] Catalyst Preparation. Catalysts were prepared in a manner
analogous to that of Example 1, differing only in the amounts of
Cp.sub.2ZrCl.sub.2 and MAO activator used. These catalyst
preparations are summarized in Table 1.
[0043] Copolymerization. The reactor was prepared as in Example 1
except nitrogen was used to fill the reactor before the addition of
liquids. After the addition of toluene, 50 milliliters of butene
were added and the reactor temperature was allowed to equilibrate
at 90.degree. C. A base pressure of 25 psig (273 kPa) was recorded.
Ethylene was added to bring the total equilibrium system pressure
to 125 psig (963 kPa), or alternatively stated, to produce an
ethylene partial pressure of 100 psia (688 kPa). 10 minutes after
catalyst injection, reaction was terminated by cooling and addition
of methanol. 64 grams of ethylene/butene copolymer were isolated
after drying.
Examples 9-10
[0044] Catalyst Preparation. The amounts of Cp.sub.2ZrCl.sub.2
catalyst and MAO activator used in Examples 9-10 are summarized in
Table 1. Addition tubes and catalyst solutions were prepared using
the methods of Example 1.
[0045] Copolymerization. Following the methods of Example 8,
nitrogen, solvent, and butene were added to the reactor and heated
to 90.degree. C. Base pressure was recorded and the ethylene
pressure regulator was set to add ethylene so as to raise the
equilibrium partial pressure of ethylene to 100 psia (689 kPa).
After saturating the system with ethylene (as measured by zero
ethylene uptake), the catalyst was injected. Reaction was
terminated by methanol addition after the elapsed times of Table
1.
Example 11
[0046] Catalyst Preparation. An aliquot of 2.5 milliliters of 10%
MAO in toluene was added to the stainless steel catalyst addition
tube prepared as above. Next, 2 milliliters of a toluene solution
containing 0.5 milligrams of
(C.sub.5Me.sub.4SiMe.sub.2NC.sub.12H.sub.23)TiCl.sub.2 (tetra
methylcyclopentadienyl) dimethylsilyl (cyclododecamido) titanium
dichloride, per milliliter was added to the addition tube.
[0047] Homopolymerization. Polymerization was performed using
essentially the same procedures as Example 1, except using the
conditions specified in Table 1. After drying, 17 grams of
homopolymer were obtained.
Examples 12-15
[0048] Catalyst Preparation. Catalyst and activator were prepared
using the procedures of Example 11. Only the amounts of catalyst
solution and MAO activator were different (see Table 1).
[0049] Homopolymerization. The procedures used in Examples 12-15
were identical to those of Example 11, but with slightly different
conditions summarized in Table 1.
Examples 16-19
[0050] Catalyst Preparation. Catalyst and activator were prepared
using the methods of example 11. See Table 1 for amounts of
activator and catalyst used.
[0051] Copolymerization. Solvent was added, followed by 1-butene,
to a reactor filled with nitrogen. The reactor was heated to the
desired reaction temperature (see Table 1) and the pressure was
recorded. The ethylene supply regulator was adjusted to provide
ethylene at a pressure necessary to maintain the tabulated absolute
ethylene partial pressure. The ethylene supply was then opened to
the reactor until equilibrium was reached as indicated by zero
ethylene flow. The reactor was sealed and catalyst was injected
using high pressure solvent (toluene or hexane. depending on
solvent used for reaction). After the indicated reaction times, the
product was rapidly cooled, quenched using methanol, and dried in
ambient air.
Examples 20-22
[0052] Catalyst Preparation. Toluene solutions containing 1
milligram of ((CH.sub.3).sub.2Si(C.sub.9H.sub.6).sub.2)HfCl.sub.2
dimethylsilyl bis(indenyl) hafnium dichloride, per milliliter of
solution were added to 10% MAO in toluene solutions for catalyst
formulation. Amounts used are summarized in Table 1.
[0053] Copolymerization. Copolymerization reactions employed
methods identical to those used in Examples 16-19 with the
exception of example 21 in which hydrogen was added to the reactor.
Hydrogen was supplied as follows: toluene and butene were added to
a clean reactor containing nitrogen. The reactor was heated to
90.degree. C. and the (base) pressure of 30 psig (308 kPa) was
recorded. Hydrogen was added so as to raise the system pressure to
130 psig (998 kPa) (100 psia hydrogen partial pressure (689 kPa)).
Next, the ethylene regulator was set to 230 psig (1687 kPa), so as
to provide the system with a partial pressure of 100 psia ( 689
kPa) of ethylene. Thereafter. reaction was carried out in a manner
analogous to Example 20.
Examples 23 & 24
[0054] Catalyst Preparation. Toluene solutions of
Cp.sub.2ZrCl.sub.2 and
(C.sub.5Me.sub.4SiMe.sub.2NC.sub.12H.sub.23)TiCl.sub.2 described in
Examples 1 and 11, respectively. were used. MAO (10% in toluene)
was added first to the catalyst addition tube, followed by
(C.sub.5Me.sub.4SiMe.sub.2NC.sub.12H.sub.23)TiCl.sub.2 solution and
subsequently by Cp.sub.2ZrCl.sub.2 solution.
[0055] Homopolymerization. Essentially the same procedures were
used as in Example 1. Only conditions were different (Table 1).
[0056] Polymer Analyses. The molecular weight, comonomer content,
and unsaturated-group structural distributions of the reaction
products are reported in Table 2. Unsaturated-group concentrations
(total olefins per 1000 carbon atoms) as well as vinyl group
selectivities were found to increase with decreasing aluminum:
metal ratios, all other factors being equal. Olefin concentrations
(comonomer) can be increased further by decreasing the
concentration of ethylene in solution (by decreasing ethylene
partial pressure or increasing temperature).
2TABLE 1 Reaction Condition Summary. Catalyst Ethylene Reaction
MAO** Al/Metal Hexane Toluene 1-Butene Hydrogen Time Yield Ex #
Catalyst* Amount (mg) Pressure (psi) Temp. (.degree.C.) (ml) ratio
(ml) (ml) (ml) press. (psi) (min) (g) 1c a 0.5 100 90 0.25 172 0
600 30 38 2 a 4 100 90 0.25 21.5 0 600 30 34 3 a 8 100 90 0.5 21.5
0 600 18 58 4 a 32 20 90 2 21.5 0 600 30 5c a 0.5 100 90 0.25 172
600 0 30 11 6 a 8 100 90 0.5 21.5 600 0 30 19 7 a 32 15 90 2 21.5
600 0 30 2 8c a 0.5 100 90 0.25 172 0 600 50 10 64 9c a 1 100 90
0.5 172 600 0 50 30 10 a 32 100 90 2 21.5 600 0 50 10 31 11c b 1
100 90 2.5 1375 0 600 30 17 12 b 8 20 90 0.5 34.4 0 600 5 13c b 1
100 90 2.5 1375 600 0 30 12 14 b 32 17 90 2 34.4 600 0 30 15c b 10
30 90 6 1375 600 0 20 16c b 1 100 90 1.5 825 0 600 10 30 15 17c b 1
100 90 1.5 825 0 600 50 30 22 18 b 16 100 90 1 34.4 0 600 10 30 19c
b 1 100 60 2.5 1375 600 0 50 30 21 20c c 1 100 90 0.5 316 0 600 50
30 6.5 21 c 5 130 90 1.25 158 0 600 50 100 30 36 22c c 1 100 90 0.5
316 600 0 50 30 5 23 a + b 32 + 1.5 60 90 3 31.4 600 0 60 47 24c a
+ b 1 + 1 30 90 1 212 0 600 30 *a = Cp.sub.2ZrCl.sub.2 b =
(C.sub.5Me.sub.4SiMe.sub.2NC.sub.12H.sub.2- 3)TiCl.sub.2 c =
((CH.sub.3).sub.2Si(C.sub.9H.sub.6).sub.2)HfCl.su- b.2 **MAO = 10
wt. % methylalumoxane in toluene
[0057]
3TABLE 2 Summary of Polymer Analyses. Trisubsti-tuted LCB % Olefins
Vinyl Vinyleneper Vinylidene per per mole % wt. % per 1000 Ex # Mn
MW Mw/Mn as Vinyl per 1000 C 1000 C 1000 C 1000 C butene butene C
1c 47184 101961 2.161 51.5 0.17 0.08 0.03 0.05 2 25154 55516 2.207
91.4 0.32 0.03 0 0 3 24619 54085 2.197 94.6 0.35 0.02 0 0 4 5657
14916 2.637 88.4 2.05 0.15 0.12 0 5c 39544 102041 2.580 76.0 0.19
0.04 0.02 0 6 12933 46941 3.630 89.5 0.77 0.09 0 0 7 1744 4710
2.701 85.4 10.16 0.36 0.74 0.63 8c 10222 35513 3.474 18.5 0.17 0.08
0.02 0.65 4.4 8.5 9c 10315 33214 3.220 36.1 0.35 0.09 0.36 0.17 2
3.9 10 6964 35992 5.168 64.3 2.96 0.06 0.07 1.51 3.9 7.5 11c 110000
332087 3.019 12 22124 125359 5.666 89.6 0.43 0.03 0.02 0 13c 99900
288000 2.883 14 3655 13117 3.589 86.1 2.48 0.12 0.11 0.17 15c 14087
37966 2.695 64.3 0.36 0.10 0.05 0.05 0.21 16c 57187 134710 2.356
63.2 0.12 0.02 0.05 0 17c 62704 153163 2.443 14.3 0.03 0.07 0.01
0.1 35.9 52.8 18 48611 173905 3.577 84.6 0.22 0 0 0.04 5.8 10.9 19c
190105 402985 2.120 5.9 0.01 0.02 0 0.14 31.7 48.1 20c 81835 211882
2.589 6.7 0.02 0.09 0.05 0.14 16.8 28.7 21 7014 23431 3.341 56.3
0.09 0.02 0.04 0.01 12.5 22.2 22c 63906 148475 2.323 14.6 0.06 0.11
0.06 0.18 16.1 27.7 23 4396 17467 3.973 90.0 2.71 0.12 0.18 0 24c
27359 56997 2.083 59.3 0.32 0.16 0.03 0.03
[0058] The following examples illustrate preparation of macromers
according to the invention and copolymerization of them with
copolymerizable monomers to form long-chain branched
copolymers.
Example I
[0059] Catalyst Preparation. A stainless steel catalyst addition
tube was prepared as outlined above. An aliquot of 1 milliliter of
10% methylalumoxane (MAO) solution in toluene was added, followed
by 16 mg of Cp.sub.2ZrCl.sub.2 in toluene solution. The sealed tube
was removed from the glovebox and connected to a reactor port under
a continuous flow of nitrogen. A flexible, stainless steel line
from the reactor supply manifold was connected to the other end of
the addition tube under a continuous flow of nitrogen.
[0060] Macromer Synthesis. The 1-liter reactor was simultaneously
purged of nitrogen and pressure tested using two ethylene
fill/purge cycles (to 300 psig (2170 kPa)). Then, the reactor
pressure was raised to .about.20 psig(239 kPa) to maintain positive
reactor pressure during setup operations. Jacket water temperature
was set to 90.degree. C. and 600 milliliters of toluene were added
to the reactor. The stirrer was set to 750 rpm. Additional ethylene
was added to maintain a positive reactor gauge pressure as gas
phase ethylene was absorbed into solution. The reactor temperature
controller was set to 90.degree. C. and the system was allowed to
reach steady state. The ethylene pressure regulator was next set to
20 psig and ethylene was added to the system until a steady state
was achieved as measured by zero ethylene uptake. The reactor was
isolated and a pulse of toluene pressurized to 300 psig (2170 kPa)
was used to force the catalyst solution from the addition tube into
the reactor. The 20 psig (239 kPa) ethylene supply manifold was
immediately opened to the reactor in order to maintain a constant
reactor pressure as ethylene was consumed by reaction. After 8
minutes of reaction, the reaction solution was quickly heated to
150.degree. C. for 30 minutes to kill the catalyst, then cooled to
90.degree. C. A small macromer sample was removed via an addition
port. Analysis by .sup.13C-NMR indicated no measurable long chain
branches were present in the macromer. The number and weight
average molecular weights of the macromer were 9,268 and 23,587
Daltons, respectively, with 81.7% of olefins as vinyls.
Example II
[0061] Branched Polymer Preparation. 25 grams of an 80.7%
norbornene in toluene solution were added to the contents of the
reactor of Example I immediately after the macromer sampling. A
catalyst addition tube containing 0.5 ml 10% MAO in toluene
solution and 1 mg CPCP*ZrCl.sub.2 was connected to the addition
port. The total pressure in the 90.degree. C. reactor was raised to
100 psig (791 kPa) by adjusting the ethylene supply regulator and
allowing the system to reach equilibrium, as indicated by zero
ethylene flow into the reactor. The catalyst was injected using a
pulse of toluene at 300 psig (2170 kPa). After 20 minutes of
reaction time, the system was quickly vented and cooled. The sample
was quenched using an excess of methanol and evaporated to dryness.
42 grams of ethylene-norbornene copolymer product containing
branched polymers with homopolyethylene branches and
ethylene-norbornene backbone were isolated. .sup.13C NMR analysis
of the product indicated 0.085 long chain branches per 1000 carbon
atoms were present.
Example III
[0062] Catalyst Preparation. A stainless steel catalyst addition
tube was prepared as outlined above. An aliquot of 2 milliliter of
10% methylalumoxane (MAO) solution in toluene was added, followed
by 32 mg of (C.sub.5Me.sub.4SiMe.sub.2NC.sub.12H.sub.23)TiCl.sub.2
in toluene solution. The sealed tube was removed from the glovebox
and connected to a reactor port under a continuous flow of
nitrogen. A flexible, stainless steel line from the reactor supply
manifold was connected to the other end of the addition tube under
a continuous flow of nitrogen.
[0063] Macromer Synthesis. The 2-liter reactor was simultaneously
purged of nitrogen and pressure tested using two ethylene
fill/purge cycles (to 300 psig) (2170 kPa). Then, the reactor
pressure was raised to about 40 psig (377 kPa) to maintain positive
reactor pressure during setup operations. Jacket water temperature
was set to 90.degree. C. and 1200 milliliters of toluene and 20 ml
of butene were added to the reactor. The stirrer was set to 750
rpm. Additional ethylene was added to maintain a positive reactor
gauge pressure as gas phase ethylene was absorbed into solution.
The reactor temperature controller was set to 90.degree. C. and the
system was allowed to reach steady state. The ethylene pressure
regulator was next set to 40 psig (377 kPa) and ethylene was added
to the system until a steady state was achieved as measured by zero
ethylene uptake. The reactor was isolated and a pulse of toluene
pressurized to 300 psig was used to force the catalyst solution
from the addition tube into the reactor. The 40 psig (377 kPa)
ethylene supply manifold was immediately opened to the reactor in
order to maintain a constant reactor pressure as ethylene was
consumed by reaction. After 25 minutes of reaction, the reaction
solution was quickly heated to 147.degree. C. for 15 minutes to
kill the catalyst, then cooled to 90.degree. C. The system was
continuously vented and purged with nitrogen to dryness so as to
remove both solvent and the ethylene and butene monomers. Then,
1,200 ml of toluene were added and the system equilibrated at
90.degree. C. A sample of the ethylene-butene macromer was removed
for analysis via the addition port. Number and weight average
molecular weights of the macromer were 22,394 and 58,119
respectively. The comonomer content of the macromer as obtained by
FTIR measurements was 6.6 mole % butene.
Example IV
[0064] Branched Polymer Preparation. The contents of the reactor of
Example III (at 90.degree. C.) were pressurized to 100 psig by
adjusting the ethylene supply regulator and allowing the system to
reach equilibrium, as indicated by zero ethylene flow into the
reactor. A catalyst addition tube containing 2 ml of 10% MAO in
toluene solution and 2 mg of
(C.sub.5Me.sub.4SiMe.sub.2NC.sub.12H.sub.23)TiCl.sub.2 in toluene
solution was connected to the addition port. The catalyst was
injected using a pulse of toluene at 300 psi. After 10 minutes of
reaction time, the system pressure was raised to 300 psig (2170
kPa). After 23 minutes of reaction time, the system was quickly
vented and cooled. The sample was quenched using an excess of
methanol and evaporated to dryness. 69.5 grams of product were
isolated and analyzed by FTIR as homopolyethylene backbones having
56 % by weight branches of the ethylene-butene macromer of Example
III.
[0065] The chain branching was measured by separating the high
molecular weight branched material from the low molecular weight
macromer using GPC methods and then quantifying by FTIR the amount
of the butene in both the macromer and the high molecular weight
branched polymer. Thus the average butene content in the branched,
high molecular weight material was 3.7 mole %, as opposed to that
of the macromer product at 6.6 mole % butene. The branching level
was calculated from the following equation: 3 wt % branches = %
butene in the high M W fraction % butene in the macromer fraction
.times. 100 % .
4TABLE 1 Reaction Condition Summary. Ethylene Catalyst Partial
Norbornene Amount Pressure Reaction MAO** Al/Metal Toluene 1-Butene
(80.7% in Time Yield Ref. # Catalyst* (mg) (psi) Temp. (.degree.C.)
(ml) ratio (ml) (ml) toluene) (min) (g) I a 16 20 90 1 34.4 600 --
-- 8 -- II b 1 100 90 0.5 275 600 -- 25 g 20 42 III c 32 40 90 2
34.4 1200 20 -- 25 -- IV c 2 100/300 90 2 550 1200 -- -- 23 69.5 *a
= Cp.sub.2ZrCl.sub.2; b = Cp((Me.sub.5)Cp)ZrCl.sub.2; c =
(C.sub.5Me.sub.4SiMe.sub.2NC.sub.- 12H.sub.23)TiCl.sub.2 **MAO = 10
wt. % methylalumoxane in toluene
* * * * *